Southern Corn Rootworm
Diabrotica undecimpunctata howardi (Barber)

PLANTS ATTACKED: Corn, grain sorghums and many other cultivated crops.

DESCRIPTION: Adult.. The adult of the southern corn rootworm is called the spotted cucumber beetle. It is about 1/4 inch long, is yellowish-green and has 11 conspicuous black spots on the wing covers.

Larva. It is about 1/2 to 3/4 inches long, has a yellowish-white body, three pairs of very small legs and a brownish head. It burrows into the germinating seeds, roots and crowns of sorghum plants.

LIFE HISTORY: This insect passes the winter in the adult stage in shelters in or near fields that afford protection from adverse weather. Adults may be active throughout the year in southern regions of Texas. Hibernating beetles become active during early spring. The female lays eggs in the soil at the base of plants. There are two generations annually.

DAMAGE: The young larva bores in the roots and underground parts of the stems of the host plants. Rootworms reduce stands and plant vigor. Another symptom is “dead heart” in young plants. On seedling plants the damage is a small hole in the crown of the plant just below the soil surface. On older plants, root pruning is the primary damage.